The present invention relates to magnetic hard disk drives. More specifically, the present invention relates to a method of mounting a slider and a micro-actuator on a head arm assembly.
In the art today, different methods are utilized to improve recording density of hard disk drives. FIG. 1 provides an illustration of a typical disk drive with a typical drive arm 102 configured to read from and write to a magnetic hard disk 104. Typically, voice-coil motors (VCM) 106 are used for controlling a hard drive's arm 102 motion across a magnetic hard disk 106. Because of the inherent tolerance (dynamic play) that exists in the placement of a recording head 108 by a VCM 106 alone, micro-actuators 110 are now being utilized to ‘fine-tune’ head 108 placement. A VCM 106 is utilized for course adjustment and the micro-actuator 110 then corrects the placement on a much smaller scale to compensate for the VCM's 106 (with the arm 102) tolerance. This enables a smaller recordable track width, increasing the ‘tracks per inch’ (TPI) value of the hard drive (increased drive density).
FIG. 2 provides an illustration of a micro-actuator as used in the art. Typically, a slider 202 (containing a read/write magnetic head; not shown) is utilized for maintaining a prescribed flying height above the disk surface 104 (See FIG. 1). Micro-actuators may have flexible beams 204 connecting a support device 206 to a slider containment unit 208 enabling slider 202 motion independent of the drive arm 102 (See FIG. 1). An electromagnetic assembly or an electromagnetic/ferromagnetic assembly (not shown) may be utilized to provide minute adjustments in orientation/location of the slider/head 202 with respect to the arm 102 (See FIG. 1).
Illustrated in an upside-down orientation, FIG. 3 describes one embodiment of a hard disk drive head gimbal assembly (HGA) with a ‘U’-shaped micro-actuator. In one embodiment, a slider 302 is bonded at two points 304 to a ‘U’-shaped micro-actuator 306. In a further embodiment, the ‘U’-shaped micro-actuator has a piezoelectric Lead Zirconate Titanate (PZT) beam (arm) 308 on each side of a Zirconia support frame (actuator base) 310. The micro-actuator 306 is coupled to a suspension 312.
Developing a method of coupling the micro-actuator to the HGA without distortion is difficult. Distortion of the micro-actuator can weaken its structure, reducing effectiveness and making the micro-actuator more vulnerable to shocks. Distortion can also increase the likelihood of particle generation. What is needed is a micro-actuator design that allows for several variations without sacrificing shock performance or increasing particle generation.